if possible self make them ask questions if the thing don too dey convincing, make they for know if true stuff or not, like that go also help people to avoid those scammers ways too.
You know most times when you will get to know what those who register with Ponzi are doing is when they will come to you to market you into the scheme. They don't ask before they go into it. It is after they have been there and not seeing what they were told then they can begin to share such information with you and by then it would have been late. I got to know about this new Ponzi because the person was scammed in the previous one and has decided to get lost money back. It is an unfortunate condition of bad economy that cause some people to try their hands in certain things that they would originally not do ( I mean those falling for it).
Meanwhile, government keeps talking about going after the owners of Ponzi scheme but no seriousness in that.